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Conclusions Good data from all Merlin sensors –Electrons/charging rates measured at three shielding depths –Total dose at two shielding depths –> 40 MeV protons (500 keV deposition threshold to be sure of protons) –LET spectrum (background) Numerous electron enhancement events have been observed via the charging (electron deposition) and total dose effects Clear 27 day interval in electron enhancements (persistent coronal holes) April ‘event’ was the most severe so far –‘worst case’ events are of engineering significance and their magnitude needs to be captured –April event still produced less than DICTAT ‘worst case’ predicted charging currents for the plates

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…..conclusions Ionising dose is delivered in surges during the electron events From Jan to August 2006, approximately half of the dose was delivered by just one electron event Dose at 6mm shield depth (Merlin +z direction) observed is greater than the predicted value (using AE8/sectored shielding models) at this stage: however may not be typical of whole solar cycle Post-script –2 nd Merlin for NASA ‘Living with a Star’ now built & qualified